Hello,
I already checked with different versions- unfortunately no luck with that. But even if it would help, it wouldn’t help me a lot as you can see from thread ( Mars Facemask weird behavior on iOS ) - I don’t have a lot of alternatives when it comes to versions… Also tried the approach with the “Symlink Unity Libraries” - also no luck.
Running it with ARFoundation, ARKit, ARKit Facetracking without Mars - same result. The same error keeps popping up 
Any other suggestions to get this fixed? Looking forward hearing from you! Thanks!!!